arm64: KVM: Increment PC after handling an SMC trap
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Web: https://git.kernel.org/torvalds/c/f5115e8869e1dfafac0e414b4f1664f3a84a4683 Commit: f5115e8869e1dfafac0e414b4f1664f3a84a4683 Parent: 20e8175d246e9f9deb377f2784b3e7dfb2ad3e86 Refname: refs/heads/master Author: Marc Zyngier <[email protected]> AuthorDate: Tue Feb 6 17:56:07 2018 +0000 Committer: Catalin Marinas <[email protected]> CommitDate: Tue Feb 6 22:53:52 2018 +0000 arm64: KVM: Increment PC after handling an SMC trap When handling an SMC trap, the "preferred return address" is set to that of the SMC, and not the next PC (which is a departure from the behaviour of an SMC that isn't trapped). Increment PC in the handler, as the guest is otherwise forever stuck... Cc: [email protected] Fixes: acfb3b883f6d ("arm64: KVM: Fix SMCCC handling of unimplemented SMC/HVC calls") Reviewed-by: Christoffer Dall <[email protected]> Tested-by: Ard Biesheuvel <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Catalin Marinas <[email protected]> --- arch/arm64/kvm/handle_exit.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 520b0dad3c62..5493bbefbd0d 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -62,7 +62,16 @@ static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) { + /* + * "If an SMC instruction executed at Non-secure EL1 is + * trapped to EL2 because HCR_EL2.TSC is 1, the exception is a + * Trap exception, not a Secure Monitor Call exception [...]" + * + * We need to advance the PC after the trap, as it would + * otherwise return to the same address... + */ vcpu_set_reg(vcpu, 0, ~0UL); + kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); return 1; } -- To unsubscribe from this list: send the line "unsubscribe git-commits-head" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html